The handing of H+ by the colon: the biophysical aspect of esophageal replacement

Comparative evaluation of acid- and bile-induced damage to pedicled jejunal or colonic segments in the rat

The choice of the esophageal substitute after surgical resection for peptic stricture lies between the colon and jejunum. The current study was designed to compare long-term resistance of the colonic and jejunal mucosa to gastric or mixed duodenogastric secretions. The following preparations were performed in Wistar rats: transposition of a colonic or jejunal patch (a) to the gastric body, with or without truncal vagotomy, or (b) to the gastric antrum and proximal duodenum, with or without truncal vagotomy. Jejunal and colonic patches were removed 4, 8, and 12 months after surgery. The only damage to the transposed mucosae was the alteration of microvilli. The alteration was more severe in colonic than in jejunal patches and was prevented by truncal vagotomy. Long-term resistance of the transposed mucosae to the environmental challenge may depend on their adaptation potentiality, involving both specific and nonspecific mechanisms. Nonspecific mechanisms include the increased production of mucus and the gastric-like transformation of the superficial epithelial layer. Specific mechanisms include the reduction of the mucosal surface size for jejunal segments and the shifting in mucin secretion patterns for colonic segments.

Radiology of colonic interposition and its associated complications

A retrospective review of the medical records, pathology reports, and radiographic studies of 81 patients who had undergone colonic interposition was undertaken, with special attention to postoperative complications. Both early (within 30 days postoperatively, 81 patients) and late (later than 30 days postoperatively, 57 patients) complications were reviewed. Early findings included anastomotic narrowing (18 patients), anastomotic leak (13), aspiration (11), and ischemic necrosis of the colon (3). Late findings included aspiration (9 patients), anastomotic strictures (8), gastric stasis (6), redundancy and tortuosity of the colon (5), anastomotic ulcers (4), gastrocolic reflux (3), and gastroesophageal reflux into the residual esophagus (2).

[Esophageal replacement]

The procedure of first choice for esophageal replacement is gastric interposition. Alternatively the replacement by colon is possible after gastric surgery. In our own examinations patients with gastric interposition had an accelerated emptying while those with colon interposition showed a delayed emptying. In spite of persisting acid secretion of the interpositioned stomach the gastroesophageal reflux was of minor importance after total intrathoracic position of the stomach.

Healing of experimental defects on the stomach: influence of autologous and heterologous materials

This study was undertaken to evaluate the influence of various autologous and heterologous structures on gastric defect healing. In 210 rats, standard gastric defects were closed using the following structures as patches: (1) pedicled colonic patches, (a) mucosal layer to lumen, and (b) peritoneal surface to lumen; (2) leiomuscular colonic buttons; and (3) lyophilized bovine tendon collagen sponges. The specimens were removed from the defect areas at standard time intervals ranging from 2 to 12 months after surgery; the samples were then examined by light microscopy (hematoxylin-eosin; Azan Mallory; Grimelius methods) and by transmission and scanning electronmicroscopy. The colonic mucosa appeared to be the most resistant of the structures to gastric secretions; it showed no mucosal disruption during the entire period of observation and also underwent a progressive gastric-like morphological transformation. In all the other cases, the healing process involved the initial development of granulation tissue followed by scar tissue with gastric mucosa growing over the scar tissue to fill the defects.